This invention relates to improved means and methods for translating between different number systems employed in a data processor.
As is well known, digital computers typically require means and methods for converting between different number systems. Conversions between binary coded decimal numbers and binary numbers, and vice versa, are probably the most frequent types of conversions required.
In the binary system of notation, each binary digit (bit) represents a different power of 2. For example, in binary notation, the binary number 11101 is equal to 1.times.2.sup.4 +1.times.2.sup.3 +1.times.2.sup.2 +0.times.2.sup.1 +1.times.2.sup.0 =29. In the binary coded decimal (BCD) system of notation, each decimal number is represented by a corresponding binary code of four binary bits. Thus, the above decimal number 29 is represented in BCD notation as 0010 1001 where 0010=2 and 1001=9.
Various known approaches for providing number conversions and, in particular, BCD to binary and/or binary to BCD conversions, are described and referenced in the articles: "A Method for High Speed BCD-to-Binary Conversion", L. C. Beougher, Computer Design, March 1973, pp. 53-59; and "Binary-to-BCD Conversion with Complex IC Functions", J. R. Linford, Computer Design, September 1970, pp. 53-61.